Add ServiceWorker InstallPhaseEvent.waitUntil() layout test.

LayoutTests/http/tests/serviceworker/controller-on-reload.html

Index: LayoutTests/http/tests/serviceworker/controller-on-reload.html
diff --git a/LayoutTests/http/tests/serviceworker/controller-on-reload.html b/LayoutTests/http/tests/serviceworker/controller-on-reload.html
index 9e8d282bcc993319f671d799d7f1c6a226952e4c..a91ea6db3df036309907a966ad9cbb91450d86cd 100644
--- a/LayoutTests/http/tests/serviceworker/controller-on-reload.html
+++ b/LayoutTests/http/tests/serviceworker/controller-on-reload.html
@@ -30,7 +30,7 @@ t.step(function() {
 
         function onRegister(worker) {
             worker.addEventListener('statechange', t.step_func(function(event) {
-                if (event.target.state == 'active')
+                if (event.target.state == 'activated')
                     onActive();
             }));
         }